Alternate action switch mechanism



April 25, 1967 c. R. STEVENS ALTERNATE ACTION SWITCH MECHANISM 2 Sheets-Sheet 1 Filed Feb. 10, 1965 INVENTOR. EURTISR. STEVENS.

April 25, 1967 c. R. STEVENS ALTERNATE ACTION SWITCH MECHANISM 2 Sheets-Sheet 2 Filed Feb. 10, 1965 4 INVENTOR.

CURTIS H. STEVENS.

ATTYS.

United States Patent 3,315,535 ALTERNATE ACTION SWITCH MECHANISM Curtis R. Stevens, La Mirada, Califi, assignor to Master Specialties Company, Gardeua, Calif., a corporation of California Filed Feb. 10, 1965, Ser. No. 431,599 2 Claims. (Cl. 74-100) This invention relates to an alternate action mecha nism; and more particularly to a simplified switch structure whose contacts are alternately closed and opened on successive inward movements of a push button.

An object of the present invention is the provision of a new and improved alternate action mechanism which involves a minimum of simple and rugged parts, which is inexpensive to manufacture, and which can be neatly arranged in a switch structure to provide the above described alternate closing and opening of its contacts upon successive inward movements of a push button.

The invention resides in certain constructions and combinations and arrangements of parts; and further objects and advantages of the invention will become apparent to those skilled in the art to which it relates from the following description of a preferred embodiment described with reference to the accompanying drawings forming a part of this specification, and in which:

FIGURE 1 is a horizontal sectional view taken approximately on the line 11 of FIGURE 2 through a switch structure embodying principles of the present invention;

FIGURE 2 is a sectional view taken approximately on the line 22 of FIGURE 1;

FIGURE 3 is a view similar to FIGURE 2 but showing the switch structure in the location it assumes when the push button is pressed to its innermost position;

FIGURE 4 is a sectional view taken along the line 44 of FIGURE 2 and with a portion broken away to better illustrate the construction beneath the plane on which the section is taken;

FIGURE 5 is a sectional view taken approximately along the line 5-5 of FIGURE 4 and with portions broken away to better illustrate details of construction beneath the plane of the viewthe view shows the inner switch closing position of the alternate action mechanism in solid lines, the outer position of the alternate action mechanism by means of dashed lines, and the innermost limit of movement by dot-dashed lines;

' FIGURE 6 is an isometric view of the cam block structure shown in the above mentioned views;

FIGURE 7 is an isometric view showing the spring and its retaining plate which cooperates with the cam block of FIGURE 6 to hold the cam block in its inner actuated position, and which illustrates the various positions assumed by the spring by means of dot-dashed lines;

FIGURE 8 is an isometric View similar to FIGURE 7 showing another embodiment of a latch spring and its retainer;

FIGURE 9 is a fragmentary isometric view of the front of the switch illustrating an on-oif indicating device;

FIGURE 10 is a fragmentary isometric view similar to FIGURE 9 but showing the on-off device in the on position; and

FIGURE 11 is an isometric view of a part of the onoif indicating device shown in FIGURES 1-3, 9 and 10.

The switch structure shown in the drawings generally comprises a pair of switch blocks 10 each of which contain contacts therein( not shown) one of which is closed and the other of which is opened when the contact actuating buttons 12 are pushed to their inner positions shown in FIGURE 2. The condition of the contacts is, of

Patented Apr. 25, 1967 course, reversed when the contact actuating buttons 12 are allowed to return to their outer position shown in FIGURE 3. The switch blocks 10 are secured between the legs 14 of a U-shaped bracket 16 by means of a pair of through bolts 18, and a snap actuation mechanism 20 is interpositioned between the switch blocks 10 and the closed end 22 of the U-shaped bracket 16. The snap actuation mechanism 20 comprises a switch button actuator 24 one end of which is pivoted to the legs 14 for tilting movement and an intermediate portion of which abuts the contact actuating buttons 12 to move them between their outer and inner positions shown in FIG- URES 3 and 2, respectively. The switch button actuator 24 is snap actuated between its inner and outer positions by means of an actuating arm 26 which is pivoted to the opposite side of the legs 14 from the pivotal connection of the switch button actuator 24, and a compression snap actuation spring 28 is interpositioned between the free ends of the switch button actuator 24' and the actuating arm 26. This mechanism is of a well-known type and will move the switch button actuator 24 from the position shown by the solid lines in FIGURE 2 to the position shown by means of solid lines in FIGURE 3 when the actuating arm 26 is moved to its inner position. The above described structure is adapted to be snapped onto and off of the following described structure which includes an alternate action mechanism 34, best seen in FIGS. 4 through 7, for moving the actuating arm 26 between the above described positions.

The portion of the switch structure which contains the alternate action mechanism 34 is supported within a rectangular housing 36. The inner end of the housing 36 is closed off by a terminal board 40 fixed to the housing by crimped portions not shown. Four spring loaded terminals 42 project forwardly from the terminal board 40 to abut the center contacts of four lamps 44 which are supported in a lamp board 46 which is retained in position against the spring loaded terminals 42 by upper and lower pins 48 which are expanded outwardly behind inwardly bent portions 50 of the housing 36 by means of structure not shown. The lamp board 46 contains a centrally located opening 52 which slidingly receives a pin 54, the outer end of which is riveted to a generally U- shaped sheet metal lens retainer 56 into which a translucent push button lens 53 is slid sideways in a manner well-known in the art. The lens retainer 56 which is utilized as a push button is spring biased to the outer position shown in FIGURE 2, and is moved manually to its innermost position shown in FIGURE 3 in which latter position it is retained by the mechanism hereinafter described.

The U-shaped bracket 16 for the switch is supported from the housing 36 by any suitable means. In the form shown, the bracket is attached by four generally L-shaped legs 60 two of which extend rearwardly from each side of the housing 36 with their lateral portions 62 facing each other. A plastic guide plate 66 having a centrally located axially extending opening 68 therethrough is held in position between the lateral portions 62 of the legs 60 by a backing plate 70 on the inner side of the legs and a retaining plate 72 positioned on the outer face of the lateral portions 62 of the legs 60. The upper and lower edges of retaining plate 72 have rearwardly extending detents 64 thereon which snap over the closed end 22 of the U-shaped bracket 16 to hold the bracket in place.

The alternate action mechanism 34 includes a spring 74 adapted to hold the alternate action mechanism 34 in its inner position after alternate inward movements of the push button 58. While the spring 74 may be made in various ways, it is shown in the drawing as a bail like member the inner end of which, see FIGURE 7, is positioned against the outer face of the retaining plate 72 'ton occupies 1 and 2. V a

p The cain structure 90 can be formed by suitable re-, cesses in the side surface of the cam block 86, but in the embodiment shown in the drawingsis formed, as pre viously indicated, by a projection from one sidesurface and is -held in place by a spring retaining plate 76. The plates 70, 72 and 76 are secured to the lateral portions 62 'of the legs 60 by means of through rivets 78. The

spring 74 is made from a piece of spring wire which extends forwardly through a small opening 80 in the plate 7 76 positioned to the side of a large centrally located opening 82 which receives structure later to be described. Inwardly of the plate 76 the spring 74 is bent laterally and then downwardly following which the end of the spring is bent forwardly through a small "opening 84 in the plate 76. When the plate 76 is sandwiched against the retaining plate 72, the inner end of the spring 74 is firmly anchored and theouter end of the spring 74 is canti: "levered outwardly of the spring retaining plate 76.

The alternate action mechanism 34 which transfers movement from the pin 54 to the actuating arm 26 is best seen in FIGURES 4 through 7 and comprises a cam block 86 of angular cross section which is slidably received and guided in a corresponding opening 88 through the terminal board 40. A cam structure 90 projects from.

the side of the cam block 86 and one side of the opening 88 is enlarged to permit the passage of the cam structure 90 through the terminal board 40. The cam block 86 has an opening 92 communicating with its outer surface, and the end of the pin 54 projects into the openingin abutment with the bottom wall 94 of the opening 92. The cam block 86 in turnha's an inwardly formed guide' pin 96 on its inner. end which projects through the opening 68 in the plastic guide plate 66. The opening 68 provides a sliding fit for the guide pin96 to guide the a pin 96, and the inner end of the guide pin 96 is adapted to abut the switch actuating'arm 26 and move it between 'its outer and inner switch operating positions above referred to. A main'biasing coil spring 98 is positioned between the cam block 86 and guide plate 66 to bias the cam block and the push button structure to their outer positions wherein 'the flange on the cam block abuts the inner surface of the terminal board 40 and the push butthe extended position shown in FIGURES of the 'cam'blo'ck 86. As' previously indicated the cam 3 block 86 is guided for longitudinal movement along a predetermined path by sliding engagement with the side walls of the'opening 88. and by sliding engagement of r the pin 96 with the: sidewalls of theopening 68. The side surface of the block 86 on which the cam structure 90 is mounted, therefore, moves in and out. along a longitudinally extending plane. The outer end of the spring has a pin-shaped end '102 which is turned generally'p erpendicularly to. the side surface of the cam block 86 on which thecam structure 90 is mounted. The end 102 of the pin may have slight bearing contact with the side surfaceof the camblock 86 but in the embodiment shown in thedrawingis spaced a slight distance therefrom. The.

pin-shaped end 102' of the spring 74 is positioned slightly 7 inwardly of the cam structure 90 when'thecam block 86 is in its outer position. wherein the flange 100 engages the inner surface of the terminal block 40. The spring 74 is arranged to assume a normal position 104 shown by dashed lines in FIGURE 5. The pin end extension 102 a of the spring 74, therefore, would have a normal line or path106 of movement (shown by dot-dashed lines in FIGURE 55) over the surface of the cam block 86 if the spring 74 were not biased transversely to either side ,of its normal position. v 7

Referring to FIGS. and 6, the'cam structure 90 may be described as starting at a most inward first point 108 which is spaced transversely to one side of the path 106 and which has a surface 110 which proceeds outwardly and transversely to the opposite side of the line 106 to a second point 112. The cam structure 90 includes a second surface 114 which proceeds laterally towards the path 106 by a short distance to allow material for providing rigidity to the second point 112, then inwardly and laterally towardsthe path 106 to a third 7 point 116, and finally outwardly to a fourth point 118.

within the blocks 10 are of the so-called momentary action type which will only stay in their second condition so long as their actuating buttons 12 are depressed.

The point 118 is generally on the same lateral line normal to the path 106 as is the second point 112. The

portion of the second surface adjacent the fourth pointv 118 forms a lip 120 for reasons which will later be ap parent. The cam 90 further includes a third surface 122 which proceeds laterally towards the path 106 from the point llS to a short distance to allow material for providing rigidity to the point 118* and then proceeds in wardly and laterally to the first point 108 which lies on the opposite side of the'path 106; The cam structure a 90 also includes a fourth surface 124 that is spaced out-.

, wardly of the second surface 114 and is spaced therefrom V at all points by a dista nce equal to; the diameter of the pin 7 102. The fourth surface 124 includes a generally inwardly extending portion 126 which terminates at a fif-th' 1 point 128 spaced apart from the second surface 114 .b'y a distance slightly larger than .the diameter of the-pin 102 and then proceeds laterally outwardly towards the path 106 to at all times provide the clearance above referred to. 7 7 As previously explained the switchstructures' housed The buttons 12 canbe held depressed by the altemate action mechanism 34 above described, and a snap actua' 7 .tion mechanism 20' is provided 'to move the actuating buttons 12 rapidly between their inner and outer positions The operation of the switch will now be described start- 1 ing with the conditoin of the mechanism shown in FIG URES 'l and 2 wherein the switch button actuator'24 holds the actuating buttons 12 in their inner position; In

74 is'positioned laterally of the cam'structu re and the spring 74 to slide along the surface l l t) until it rides over'the top of the point 112. The pin 102 then snaps" into engagement with the surface 126 as'seen in FIGURE 3. During this inward movement, the main biasing spring 98 is "compressed, and the guide pin-96 of the cam block.

86 is forced through the opening 6 8 to compress snap actuation spring 28, move the actuating arm 26 over its toggle point, and cause the'actuator 24 to snap outwardly until it abuts the pivoted end of the actuating arm 26. The actuating arm 26 isthen free and clear of the buttons 12 which then assume their outer positions,

When inward pressure on the push button 58 is re leased, the main biasing spring 98 biases the'cam block 86 outwardly causing the pin 102 to move inwardly be-- tween'the second point 11 2 and fifth point 128, after which it snaps laterally towards the normal position'104. V of the spring and is caught by the lip as shown in full lines in FIGURE 5. The cam block 86 is thereby held by the spring 74 in the position shown in FIGURE 5 which is but a slight distance outwardly from the innermost limit of travel of the structure above described, but

which still causes the snap actuation spring 28 to bias the actuator to the outer position previously described. V A subsequent inward movement of the push button 58 causes the pin 102 to ride over the outer end of the lip '12() after which the spring 74 snaps the pin extension't o 7 its normal position 104 in line with the third surface 122.

r so that the spring structure 74 will no longer hold the cam block 86' in its ,inner position. The main biasing coil spring 98 biases the cam block 86 outwardly, and

upon relieving pressure from the push button 58, the parts are returned to the outer condition shown in FIG- URES l and 2. During movement of the cam block 86 to its outer positoin, the pin '96 allows the snap actuation spring 28 to move the actuating arm 26 outwardly past the toggle point of the switch button actuator 24 following which the snap actuation spring 28 snaps the switch button actuator 24 to the inner position shown in FIG- URES 1 and 2 wherein it presses the contact buttons 12 to their inner first described depressed position.

The embodiment of spring and spring retainer plate shown in FIGURE 8, corresponds generally to that previously described, but differs therefrom principally in the manner in which the spring is supported. Those portions of the embodiment shown in FIGURE 8 which are similar to corresponding portions of the embodiment previously described, are designated by a like reference numeral characterized further in that a prime mark is afiixed thereto. The center portion 130 of the spring 74' is coiled tightly around a laterally inwardly extending bent up leg 132 of a retainer 134 that is secured to the outer face of the retaining plate 72' by two rivets. The fixed end 136 of the spring 74' extends through an opening 138 in the retaining plate 72 directly beneath the leg 132 to anchor the inner end of the spring.

It is diflicult, when viewing the front of the switch structure from a distance, to ascertain whether the lens 58 is in the outer position shown in FIGURES l, 2, and 9, or the inner position shown in FIGURES 3 and 10. It has been found highly desirable, therefore, to provide an additional indication of the position of the lens 58, and hence the condition of switch 10. It is desired that this additional indication be provided with a minimum of mechanism, and as shown in the drawings, is accomplished by an angular strip 140 of bendable plastic material, which in the present instance is silicone rubber. The center portion of the upper wall of the lens retainer 56 is deformed inwardly to provide a recess 1 .2, as seen in FIG. 3, and the center portion of the top edge of the lens 58 is correspondingly recessed to receive the inwardly deformed portion 144 of the lens retainer 56. One leg of the angular strip 140 is glued to the top surface of the recess 142, with the other leg 146 of the strip extending upwardly. The recess 142 and strip 140 are positioned so that the leg 146 clears the front of the housing 36 when the lens retainer is in the outer position shown in FIGURES 1, 2 and 9, and so that the outer top edge of the housing 36 will bend the upwardly extending leg 146 of the angular strip 140 down out of view when the lens retainer is moved to the inner position shown in FIG- URES 3 and 10. Because the switch 19 is in an off position when the lens retainer 56 is in the position shown in FIGURES 3 and 10, the letters OFF are formed on the outwardly facing surface 148 of the strip 140, and this face is folded downwardly out of sight when the structure is in the ON position shown in FIGURES 1, 2, and 9. The angular strip 140 is made of resilient material, and when the lens 58 is depressed to snap it into its outer position shown in FIGURES 1, 2, and 9, the leg 146 snaps upwardly again to bring the face 148 into view to indicate OFF. The recess 142 is preferably limited to the center portion of the top leg of the lens retainer 56, and the portion of the top of the lens 58 which is recessed to receive the portion 144 is preferably correspondingly limited in width. By so doing, the lens 58 extends upwardly on either side of the inwardly bent portion 144 to provide retention against sideward movement of the lens 58 relative to the holder 56. The lens holder 56 is flexible, however, and when the lens holder 56 is removed from the housing 36, sideward pressure on the lens 58 will spring the top leg of the holder 56 upwardly to permit removal of the lens 58.

While the invention has been described in considerable detail, I do not wish to be limited to particular embodiment shown and described, and it is my intention to cover hereby all novel adaptations, modifications and arrangements thereof which come Within the practice of those skilled in the art to which the invention relates.

What I claim is:

1. An alternate action mechanism comprising: a support structure, a cam block guided for reciprocating movement along a given path on said support structure between outer and inner positions, spring means having a pin projecting generally perpendicularly toward one side of said cam block, said spring means supporting said pin for movement generally transversely to the path of movement of the side surface of said cam block and yieldably biasing said pin to a normal position from which the pin can be moved transversely in opposite directions, there being an imaginary line on the block formed by the normal position of said pin when said block is moved along said path, cam means on said block positioned outwardly of said pin when said block is in its outer position, said cam means having a first pin engaging surface the innermost point of which is positioned transversely to one side of said imaginary line, said first surface being inclined outwardly to a second point on the opposite transverse side of said imaginary line, said cam means having a second pin engaging surface which is outwardly of said first surface and which proceeds from said second point to a third point spaced inwardly of said second point by a distance at least equal to the diameter of said pin and then outwardly to a fourth point located to the same side of said imaginary line as said second point and at approximately the same distance outwardly of said block as said second point to provide a pin retaining lip, a third pin engaging surface proceeding from said fourth point to said first point, and a fourth surface outwardly of and between said second and fourth points and facing said second surface with its innermost portion approximately in a line connecting said second and fourth points, said fourth surface having a clearance with respect to said second surface at least as great as the diameter of said pin, and whereby said pin travels over said first, fourth and second surfaces to be retained by said pin retaining lip when said block is moved from said outer to said inner position and then a slight distance outwardly. again, and said pin moves over said third surface when said block is subsequently moved inwardly and then to its outer position.

2. An alternate action mechanism comprising: a support structure, a cam block guided for reciprocating movement along a given path on said support structure between outer and inner positions, a wire spring cantilevered from said support structure with a body portion extending generally parallel to said path of said cam block and carrying a pin projecting generally perpendicularly toward one side of said cam block, said spring supporting said pin for movement generally transversely to the path of movement of the side surface of said cam block and yieldably biasing said pin to a normal position from which the pin can be moved transversely in opposite directions, there being an imaginary line on the block formed by the normal position of said pin when said block is moved along said path, cam means on said block positioned outwardly of said pin when said block is in its outer position, said cam means having a first pin engaging surface the innermost point of which is positioned transversely to one side of said imaginary line, said first surface being inclined outwardly to a second point on the opposite transverse side of said imaginary line, said cam means having a second pin engaging surface which is outwardly of said first surface and which proceeds from said second point to a third point spaced inwardly of said second point by a distance at least equal to the diameter of said pin and then outwardly to a fourth point located to the same side of said imaginary line as said second point and at approximately the same distance outwardly of said block as said second point to provide a pin retaining lip, a third pin engaging surface proceeding from said fourth point to said first point, and a fourth surface outwardly of and between said second and fourth points and facing said second surface References Cited by the Examiner with its innermost portion approximately in a line connecting said second and fourth points, said fourth surface UNITED STATES PATENTS V having a clearance with respect to said second surface 1,264,529 4/ 19 18 Kocourek 74-100 at least as great as the diameter of said pin, and whereby 5 7 2,946,237 7/ 1960 Hebert 'said pin travels over said first, fourth and second sur- FOREIGN PATENTS said block is moved from said outer to said inner posi- ,pin moves over said third surface when said block is faces to become retained by said pin retaining 11p when ,1 7/1964 Germanyt1on and then a slight distance outwardly again, and said FRED C- M ATTERN, Primary Examiner;

subsequently moved inwardly and then to its outer W. S. RATLIFF, Assistant Examiner. position. 

1. AN ALTERNATE ACTION MECHANISM COMPRISING: A SUPPORT STRUCTURE, A CAM BLOCK GUIDED FOR RECIPROCATING MOVEMENT ALONG A GIVEN PATH ON SAID SUPPORT STRUCTURE BETWEEN OUTER AND INNER POSITIONS, SPRING MEANS HAVING A PIN PROJECTING GENERALLY PERPENDICULARLY TOWARD ONE SIDE OF SAID CAM BLOCK, SAID SPRING MEANS SUPPORTING SAID PIN FOR MOVEMENT GENERALLY TRANSVERSELY TO THE PATH OF MOVEMENT OF THE SIDE SURFACE OF SAID CAM BLOCK AND YIELDABLY BIASING SAID PIN TO A NORMAL POSITION FROM WHICH THE PIN CAN BE MOVED TRANSVERSELY IN OPPOSITE DIRECTIONS, THERE BEING AN IMAGINARY LINE ON THE BLOCK FORMED BY THE NORMAL POSITION OF SAID PIN WHEN SAID BLOCK IS MOVED ALONG SAID PATH, CAM MEANS ON SAID BLOCK POSITIONED OUTWARDLY OF SAID PIN WHEN SAID BLOCK IS IN ITS OUTER POSITION, SAID CAM MEANS HAVING A FIRST PIN ENGAGING SURFACE THE INNERMOST POINT OF WHICH IS POSITIONED TRANSVERSELY TO ONE SIDE OF SAID IMAGINARY LINE, SAID FIRST SURFACE BEING INCLINED OUTWARDLY TO A SECOND POINT ON THE OPPOSITE TRANSVERSE SIDE OF SAID IMAGINARY LINE, SAID CAM MEANS HAVING A SECOND PIN ENGAGING SURFACE WHICH IS OUTWARDLY OF SAID FIRST SURFACE AND WHICH PROCEEDS FROM SAID SECOND POINT 